Rabies diagnosis in animals

The direct fluorescent antibody test (dFA) is most frequently used to diagnose rabies. This test can be performed on brain tissue of animals suspected of being rabid.

Rabies diagnosis in humans

Several tests are necessary to confirm or ruleout rabies in a human intra-vitam (while living). No single test can be used to ruleout rabies in humans with certainty. Tests are performed on samples of serum, spinal fluid, skin biopsies from the nape of the neck, and saliva. Routinely, serum and spinal fluid are tested for antibodies to rabies virus. The skin biopsy specimen is examined by dFA for the presence of rabies antigen in cutaneous nerves at the base of hair follicles. Saliva maybe tested by virus isolation or nested reverse transcription polymerase chain reaction (RT-PCR) methods.

The importance of routine rabies tests

The rapid and accurate laboratory diagnosis of rabies infections in humans and other animals are essential for timely administration of postexposure prophylaxis. Within a few hours, a diagnostic laboratory can determine whether or not an animal is rabid and inform the responsible medical personnel. The laboratory results may save a patient from unnecessary physical and psychological trauma, and financial burdens, if the animal is not rabid. In addition, the laboratory identification of positive cases may aid in defining current epidemiologic patterns of rabies and in recognizing the need for the development of rabies control programs.

Information courtesy of the Centers for Disease Control.